Add Two PCI & Two PCI Express Expansion Card Slots to a Desktop or Laptop Computer System. The PEX2PCIE4L PCI/PCI Express Expansion Chassis provides a quick and simple I/O expansion solution to almost any PCI Express (PCIe) enabled system. Adding PCI/PCIe cards to a server or workstation, or providing a platform to swap cards between a mobile and desktop setup is a cost-effective and time-saving solution for maximizing the I/O capabilities of your system.The external expansion chassis adds two full-length (38cm) PCI slots (32-bit/33MHz), as well as two PCIe x1 (single-lane) slots to a host computer through a single PCI Express connection. Providing total bandwidth up to 250MBps from the PCIe x1 host controller card allows the computer to function as though the expansion chassis cards were connected directly to the motherboard.Backed by a StarTech.com 2-year warranty and free lifetime technical support.